The first thing that struck me about this 1905 gown was the black piping. This, my friends, is why velvet is one of the coolest materials known to mankind. Because of all the little fibers (making velvet is kind of like making a carpet) it soaks up light. So you get this deep, saturated black you'd not get otherwise. Plus, it's silk, so it would shimmer in the right light, too. The physics of velvet is so lovely.
Secondly, this dress just screams 1905. From the 1890s to the 1920s, fashion moved FAST. What we see here is the last gasp of that S shape corset as we head toward reformation dresses and the looser look of the 1920s. Though the lace is definitely a bit stained from its age, it's not hard to imagine this dress when it was shiny and new. The slight train and the blocking of lace and pattern just make this so whimsical. Not to mention those 18th century inspired sleeves! I think she's just a darling.
A Room with a View / Helena Bonham-Carter as Lucy Honeychurch
Year: 1986
Designer: Jenny Beavan and John Bright
Lucy wears this outfit for a brief scene of tea in the garden. Some of the costumes for this film were vintage pieces, and I wonder if this might be one of them, with the intricate embroidery on the top (does it qualify as a shirtwaist?). I also wonder if it might have been chosen as a nod to the original novel, where the famous kiss in the flower field happens in spring rather than summer, and the flowers are violets rather than poppies.
There's a very good writeup of the costumes in this film here.